Preparation and Properties of an Alginate-Based Fiber Separator for Lithium-Ion Batteries

• DOI: 10.1021/acsami.0c10630
• Publication Date: 2020-08-03T15:04:23Z
• Authors: Liwen Tan; Zhenxing Li; Ran Shi; Fengyu Quan; Bingbing Wang; Xiaomei Ma; Quan Ji; Xing Tian; Yanzhi Xia
• Keywords: 02 engineering and technology; 0210 nano-technology; 01 natural sciences; 7. Clean energy; 0104 chemical sciences

The membrane is one of the key inner parts of lithium-ion batteries, which determines the interfacial structure and internal resistance, ultimately affecting the capacity, cycling, and safety performance of the cell. In this article, an alginate-based fiber composite membrane was successfully fabricated from cellulose and calcium alginate with flame-retardant properties via a traditional papermaking process. In the membrane, the calcium alginate plays a bridging role and the cellulose acts as a filler. After 100 cycles, lithium-ion batteries by the alginate-based fiber separator exhibited better capacity retention ratios (approximately 90%) compared with those of commercial PP separators. Furthermore, the alginate-based fiber separator demonstrated fine thermal stability and electrochemical properties, showing a stable charge-discharge capability and no hot melt shrinkage at higher temperatures, which is a breakthrough in improving the safety of the cell. This research affords a new way for the large-scale fabrication of safe lithium-ion battery separators.